Regulator



y 1940. L.,.J. ADAMS El AL 2,200,352

REGULATOR Filad Oct. 22, 1937 39 INVENTORS gs LELAND -J.ADAM5 2 BY FRANK BQACKEN ATTORNEY Patented May 14, 1940 PATENT OFFICE aaeumroa Leland J. Adams, Burbank, and Frank Bracken, Los Angeles, Calif., assignors to Warner Bros. Pictures, Inc.,- New York, N. Y., a corporation of Delaware lpplication October 22, 1937, Serial No. 170,436

' 3 Claims.

This invention relates to regulators for use with motor driven electric generator units and has particular reference to electro-magnetic regulators or governors for automatically regulating the speed and torque of an internal combustion engine, or other prime mover driving a generator, in accordance with the current load on the generator.

As is well known in the art, the voltage output 10 of a. constant speed shunt, series or compound generator varies with the current load, except in the case of special compound wound generators. This variation in voltage is very objectionable in many current consuming systems of which x illuminating systems having a varying number of lamps in circuit are notable examples.

One object of the present invention is to automatically regulate the output, preferably the voltage, of an electric generator.

A further object is to maintain the voltage output of a generator constant for varying current loads on the generator.

A further object of the invention is to provide a relatively large movement of a controlling element of an electric regulator.

The accomplishment of the above and other objects of the invention will be apparent from the following description in conjunction with the accompanying drawing wherein:

Fig. 1 is an elevational view of a motor driven generator unit embodying the present invention.

Fig. 2 is a sectional view through the electric regulator.

Fig. 3 is a fragmentary view, partly in section, showing the fuel inlet valve of the engine 35 and its various operating connections.

Fig. 4 is a sectional plan view taken along the line 4-4 of F18. 3.

Referring particularly to Fig. 1 the generator unit comprises an internal combustion engine '40 III, which is shown in the illustration as a. gasoline engine having a crankcase H, a cylinder block [2, a fuel inlet manifold l3, connected in the usual manner to the cylinders (not shown) in the cylinder block H, a carburetor l4, and a tube or conduit l5, forming part of the manifold l3 and interconnecting the carburetor l4 with the inlet opening of the manifold l3. The crank shaft IGof the engine I is connected to the 50 shaft ll of a shunt wound generator I8 through a coupling l9.

As shown inI'lgs. 3 and 4, the fuel inlet valve 20 of the engine is of the butterfly type and is Y rotatably adjustable withinthe conduit by a formed on diametrically opposite sides of the conduit l5. An arm 24, securely mounted at one end thereof as by a pin 25 to the exterior portion of the shaft 2|, is pivotally connected at its opposite bifurcated end to a vertically ex- 5 tending link 28 by means of a clevis pin 21. Link 28 has a plurality of spaced bearing holes 29 therein whereby the position of the pivotal connection between the arm 24 and link 28 may be changed. The lower end of the link 28 is pivotally mounted to the extending end of an actuating lever 26 as shown in Fig. 1.

Referring now to both Figs. 1 and 2, the lever 26 is pivotally mounted by means of a clevis pin 30 to the upwardly extending bifurcated portion 3| of an extension 32 formed integrally with a vertically extending core 33 of soft iron, or the like, forming part of the electric regulator to be now described. The core 33 is rigidly secured in relation to the crankcase II of the engine l0 through an angle bracket 34. Bracket 34 is secured to the crankcase H by bolts 35 and is secured to the lower end of the core 33 by bolts 36. A solenoid 31 is mounted upon a spool consisting of fiber flanges 38 and 39, and a sleeve 40, also of fiber, or like material, such spool being securely mounted in any suitable manner on the lower end of the core 33. A second solenoid 4| is mounted on a similar spool comprising flanges 42 and 43, and a sleeve 44. This second spool, however, is slidable vertically along the core 33 to and from the lower solenoid 31.

The windings of the two solenoids 31 and 4| are connected in series with each other and are wound in opposite directions so that the polarity of the magnetic field produced by one of the solenoids opposes that of the other solenoid. Therefore, on application of current through the two solenoids the upper solenoid 4| will be raised against the force of gravity by an amount depending on the current passing through the solenoids. The solenoids 31 and 4| may, however, be connected in parallel or other circuit relation with each other with their magnetic polarities in opposition to produce the same effect.

A ring shaped flange 45, surrounding the core 45 33, is secured as by screws 46 to the upper flange 42 of the movable solenoid 4|. An upwardly extending lug 41 formed integrally with the flange 46 is pivotally connected to a vertically extending link 48 by a pin 49. The upper end of the link 48 is pivotally secured by means of a pin 5|] to a point on the lever 26.

A third coil 5| comprising a small number of turns of heavy conductor wire is wound around the lower solenoid 31 and is secured thereto in any suitable manner, as by being tightly wrapped. This coil 5| is placed in series with the load circuit, generally indicated at 52, of the generator l8 (Fig. 1) and has its polarity opposed to that of solenoid 31. The two solenoid windings 31 and 4|, in series with each other, are connected in shunt with the load circuit 52 as diagrammatically shown by the connections 53 and 54.

A rheostat 56 is provided in series with the windings of the solenoids 31 and 4| to allow adjustment required by changes in the resistance of the two solenoids 31 and 4| due to temperature variations therein as well as to vary the voltage level of the generator output circuit.

The load circuit 52 of the generator may be used to supply current to any electrical device. However, in this case it is shown as supplying current to a number of lamps diagrammatically indicated at 55.

The weight of the movable solenoid 4| is such as to move the valve 20, through the force of gravity, toward an open position when the opposing magnetic force between the solenoids 31 and 4| is decreased.

Whenever the butterfly valve 20 is opened from a closed or substantially closed position, an abnormal amount of force is required to move it into an open position due to the excessive vacuum built up within the manifold l3, especially if a high power engine is used. In order to overcome this resistance of the valve a vacuum booster generally indicated at 51 is provided. The booster 51 comprises a cylinder 58 which is pivotally supported by means of a pin 59 on a bracket Gil integrally formed on the conduit I5. A flexible tubing 6| secured at its upper end at 52 to the manifold l3 and its lower end 63 to the cylinder 58 communicates the interior of the manifold l3 with the interior of the cylinder 58. A close fitting plunger 64 is movable within the cylinder 58 and is pivotally secured at 65 to the lower end of an arm 6t journalled on the valve shaft 2|. A dog 67 is securely mounted on the extending portion of the valve shaft 2| and has an adjustable screw 68 threadably mounted therein, the end of screw 58 being adapted to abut a boss 69 formed on the arm '88.

When the butterfly 20 is in a closed or substantially closed'position, as in a no load condition of the generator, the vacuum produced in the manifold i3 is transmitted through the tubing BI to the cylinder 58, thereby producing a pull on the plunger 64 tending to open the valve 20. The size of the cylinder 58, however, is such that the vacuum produced in the manifold H is insunicient in itself to effect movement of the valve 20, but overcomes the excessive resistance oifered to movement of the valve 20 due to the high vacuum in the manifold. It will be noted that the end of plunger 64 is adapted to abut the inlet end of cylinder 58 before the valve 20 is moved to its full open position. Therefore, as plunger 64 reaches" the limit of its travel, it becomes ineffective to act upon the valve 20, the remaining movement of valve 20 being accomplished solely through the link 28.

This action of the vacuum booster 51 prevents an undue resistance from being offered to the movement of the solenoid 4|, by reason of the vacuum acting against one side of the valve 20, after the engine has been operating with the valve substantially closed, thus insuring a movement of the valve in accordance with the speed changes necessary to obtain constant voltage.

A dashpot I is provided to prevent a strain being imposed on the engine due to a sudden application of current load on the generator and also to prevent a hunting or oscillating movement of the valve 20 on a sudden change of load. Dashpot 10 comprises a cylinder 1| pivotally mounted at 12 to the cylinder block l2 and a double acting piston indicated by the dotted lines 13, movable within the cylinder H. The piston 13 is attached to an extending portion of lever 26 by means of a piston rod 14 pivotally secured at its lower end to the lever 28 to retard the movement of the solenoid 4| and consequently the butterfly valve 20. Instead of a double acting dashpot for damping any movement of the valve 20 a dashpot acting only on the opening movement of valve 2|), may be substituted, permitting the valve to be closed immediately after a load has been removed from the generator, while retarding its opening movement.

A starting control 15 is provided to control the engine l0 during starting. This control comprises a rod 16 manually shiftable. lengthwise thereof and having a slot ll formed at one of its ends. An arm 18 rigidly secured at its lower end to the valve shaft 2| has a pin 19 at its upper end adapted to ride within the slot ll of the rod 16. When the engine is started the rod I6 is pushed inward, this results in lifting coil 4| and holding valve 20 substantially closed through the engagement of the end of the slot 11 with the pin 19. The rod 16 may be also used to control the operation. of the engine independently of the electric regulator in the event that the regulator would become inoperative.

The operation of the regulating apparatus is as follows. Since the solenoids 3! and 4| are connected in series with each other and across the load circuit 52, these solenoids will be responsive to the voltage generated by the generator IS. on operation of the generator I8, the solenoid 4|, due to the opposed polarity thereof with the solenoid 31, is raised against the action of gravity an amount determined by the voltage of the current passing therethrough. The rheostat 55 is adjusted to compensate for varying resistance due to temperature changes within these solenoids or to adjust the apparatus for any desired voltage level. The interaction of the two opposed solenoids 31 and 4| produces a greater amount of bodily movement of solenoid 4| for a given change of current than is possible with the use ol 9. single solenoid only. In view of this feature, wear or looseness in the various pivotal connections of the linkage system between the movable solenoid 4| and the valve 20 has a negligible effect on operation of the engine.

As may be noted in Fig. 1 the solenoid, on raising, moves the lever 26 in a clockwise direc tion about the pin 30 and therefore, through the link 28 and arm 24, moves the valve toward a closed position to a setting which is predetermined by adjustment of the lengths of the various elements comprising the linkage between the solenoid 4| and the valve shaft 2|.

Preferably this setting is so adjusted that the speed of the engine in a no-load condition of the generator circuit will be approximately the same as when a light current load is applied to the circuit. However, the series coil may be made of such strength, and the linkage between solenoid 4| and valve 20 may be so arranged that the speed of engine I. may automatically be reduced to idling when the current load is removed from the generator.

On application of a current load on the circuit 52, the field of solenoid 31 will be weakerred by the opposing fleld of coil 5| permitting the solenoid 4| to drop a. proportional amount thus opening the valve 20, permitting the engine In to develop a higher speed so as to raise the vfoltage output of the regulator sufficient to compensate for the loss in voltage due to the increased load on the load circuit, bearing in mind that the generator is of the shunt wound type wherein at a constant speed the voltage decreases as the current load increases.

By varying the strength of the series coil 5|, the response of the engine l may be changed to suit the current-voltage-speed characteristics of the generator. For instance, if the speed of the generator has to be increased only slightly to maintain a constant voltage for a relatively large applied current load, the coil should be weaker than if a. greater increase in speed were necessitated for the same current load. The regulator may be over-compensated, if desired, by increasing the strength of coil 5| to compensate for voltage losses in the output circuit line or for other reasons. This change in response may also be obtained by varying the weight of the solenoid 4| or otherwise offering a resistance to the movement thereof.

It will be noted that the present invention obviates the necessity of using springs by employing the force of gravity on the solenoid 4|, thus insuring smooth operation without the varying and uncertain action of springs.

While we have described our invention in its preferred embodiment, we desire it to be understood that various modifications may be made therein. For example, although the invention is particularly applicable to generators of the shunt wound type, it is to be understood that it may be used equally well on a series wound or any other type generator as well, using a different linkage or other inter-connecting means between the electrical regulator and the valve 20 so as to operate the valve 20 in accordance with the current-voltage curve of the particular generator employed. For example, instead of a straight line link connection as shown, any suitable non-linear cam or like interconnection between the regulator and the fuel valve may be employed. Furthermore; for small power engines which do not require an excessive force to open the butterfly valve, the vacuum booster may be omitted.

The prime mover regulator herein shown and described is claimed in our co-pending application S. N 214,274, filed June 17, 1938 for Prime mover regulation.

We claim:

1. A regulator comprising the combination of a core, means for supporting said core upright, a fixed coil around the lower portion of said core, an opposing coil slidable on the upper portion of said core and adapted by gravity to drop close to said fixed coil, an arm supported by and extending laterally from the top of said core and forming a. pivotal support, a regulator arm pivotally connected intermediate its ends to said pivotal support, an operative connection between said slidable coil and one end of said arm, and.

a regulating element connected to the other end of said arm.

2. A regulator according to claim 1 wherein said operative connection comprises a flange on top of said slidable coil, a ring fastened to said flange, and a lug connecting said ring and said arm.

3. A regulator comprising the combination of' a core, means for supporting said core upright, a series coil and a shunt coil fixed around the lower portion of said core, an opposing shunt coil slidable on the upper portion of said core and adapted by gravity to drop close to said fixed coils, an arm extending laterally from the top of said core and forming a pivotal support, a regulator arm pivotallyconnected intermediate its ends to said pivotal support, a link connecting said movable coil to one end of said regulator arm at one side of said pivotal support, means for connecting the other end of said regulator arm at the other side of said pivotal support to a regulating element, a lever for said regulating element having a pin, a hand operating rod having an elongated slot to receive said pin, and means supporting said rod for movement to engage said pin to manually operate said regulating element and lift said movable coil.

LELAND J. ADAMS. FRANK BRACKEN. 

